Strain gauge strips, in which one side has a grid or other sensing element applied thereto have to be affixed to the structure, the strain of which is to be determined. Usually, the carrier is a plastic support of substrate on which a strain gauge grid is applied by vapor deposition or in a form of an atomized powder (see U.S. Pat. Nos. 2,556,132 and 2,621,276). The reverse side of the strip is then attached to the material structure, or frame to be tested for example by adhesion (see German Disclosure Document DE-OS 25 50 669) or welded thereon. Neither of these attachment methods are free from difficulty. Adhering the strip element is subject to undesired creep effects; welding the strip, for example already supported on another support carrier, involves the use of high temperatures which may damage and, in a limiting case destroy the strip, and additionally can lead to change in the characteristics of the measuring grid itself.